Pay-station automatic telephone system



April 22 v 1924' R. D. CONWAY PAY STATION AUTOMATIC TELEPHONE SYSTEMFiled MaIGh 23 1921 2 Sheets-Sheet l Hayfl Conway 1,491,339 Apn] 22 1924R. D. CONWAY PAY STATION AUTOMATIC TELEPHONE SYSTEM Filed March 23. 19212 Sheets-Sheet 2 EU k3d h *3 r =5 l' *T I Y V J E L a x @g P P 1% w W &

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ROY I). CONWAY, OIE CHATHAM NEW 5 COMPANY, INCORPORATED, OF NEW YORK,

PAY-STATION AUTDMA ERSEY, ASSIGNOR T0 FIESTERN ELECTRIC N. ll". ACORYORATION GE NEW YORK.

TIC TELEPHon'E sYsrnia.

Application filed March 23, 1921. Serial 1E0. 12.

T0 cZZ whom it may concern Be it known that T, ROY D. CONWAY, a citizenof United States, residing at l'lillside Avenue, Chathani, in the countyof Morris, State of New Jersey, have invented certain new and usefulImprovements in Paywtaition Automatic Telephone Systems, of which thefollowing is a full, clear, concise, and exact description.

This invention relates to machine switcln ing pay station telephonesystems andlis an improvement on the system disclosed and claimed in myapplication for Letters Patent tiled Aug. 11, 1920, Serial No.-il02,760. for coin collect systems for automatic telephone exchanges.

in the circuit arrangement of this invention the removal ot the receivercauses automatic means to extend the calling line to a trunk terminatingin a lirst selector but the subscriber cannot set the same due to theimpulse circuit being normally disabled at the central ottice. A relayat the central oliice is now intermittently operated to open theconnection of the calling line with the trunl i and connect a test.relay to the calling line to test. for a ground caused by the deposit ofthe coin in the coin box. The relay which opens the connection of thecalling; line with the trunk simultaneously closes a bridgetluereacrossto hold operated the linerelay oi the first selector inorder to prevent the automatic line switch from releasing prematurely,this switch being held operated by a ground applied to its "holdingwinding from the slow relay at the first selector.

The presence of the ground due to the deposit of the coin operates thetest relay which causes means to be actuated to connect an impulse relayto the calling line. This relay is now in circuit with the dial of thecalling line and is operated by the dial to transmit impulses to theimpulse relays oi thenumerical switches to build up the connection. Theresponse of the called party prepares ,a circuit to apply current of acertain polarit to the calling line to operate the polarized magnet inthe coin. box to collect the deposited coin, which circuit is closedupon'the replacement of the receiver by the calling party. The failureof the called party to answer prepares a circuit to apply current of theopposite polarity to the calling; line to operate the said polarizedmagnet to refund the coin, which circuit is closed upon the replacementof the receiver by the calling party.

Referring to the drawings, shows a calling line, line switch and thecoin control circuit, Fig. 2 shows a secondaryliue switch, a firstcalled line. 1 p

The invention will be most readily understood from a detaileddescription of the operation of the system.

The removal of the receiver at substation A operates the line relav 100of the wellknown Keith line switch which closes thec'ircuit of the pulldown winding 101 to cause the line switch to plunge and seize thepreselected trunk 102, 10?}, as scribed for example in Patent 1510.1,305,369 of May 20, 1919, to It. J. Ray. The-closure of contact 10%-applies ground to holding (30l1 ductor 10-3 leading to the-pull downcoil 200 of the secondary line switch SL8 causing such switch to seize apreselected 'tirst selector F .in the well-known manner. This selectormay he of the type shown in reissue Patent No. 13,901, issued Apr; 13,1915, to F. Newiforth, The seizure of the selector causes a ground to heapplied to the rcleusewirc 201 in the well-known manner. These two lineswitches thus have extended the, calling line to the first selector F51.The ground applied to the releasewire 201 operates rel this circuitincluding the inner right arnnr ture of relay Y. Tie-lay S in attractingits inner right armature applies ground to the conductor 10? leading tothe holding wind- 108 of the primary line switch and also operates slowrelay 11 which applies another ground to this wire. Relay S in operatingconnects.interrupting machine 109 to relay A to operate the same tointermittently connect test relay L to the tip and ring of the callingline to test for the presence of the coin inthe coin box. This coin boxmay he oi? the type shown in Patent No. 1,043,219, Nov. 5, 1912,to O.ll. Forsherex wherein the deposit of the coin hy closing contact 110connects the polarized magnet 111 to ground from the tip side 121 of theline. The circuit for relay A is as follows: tree pole oi battery, relay112, relay A, conductor 113, outer le'it armature and front contact ofre- .lay S, upperi'nost armature and hackcontact of relay C, outer leftarmature and normal contact of relay E, conductor 151, interrupter .109to ground. ltelay A upon its energizeselector, a connector and the shownand tie till tion connects bridges 157, 158 across the trunk 136, 137 tohold operated the impulse relay of the first selector to preventpremature release and connects test relay L to the tip and ringconductors in parallel to the coin ground, the circuit being as follows:free pole of battery, inner right armature and back contact of relay E,resistance 115, outer left armature and normal contact of relay Y, innerleft armature and front con tact of relay S, relay L, ring conductor116, lowermost armature and front contact of relay A, conductor 103,contact 117, ring conductor 118 through the receiver hook andtransmitter, contact 110, polarized magnet 111 to ground.

The path over the tip side may be traced from conductor 116 through theouter right normal contact of relay E, tip conductor 119, uppermostarmature and front contact of relay A, conductor 102, contact 120, tipconductor 121, contact 110, polarized magnet 111 to ground. Relay L inattracting its armature operates relay E, this circuit including theouter right armature and normal contact of relay B, conductor 122,armature and front contact of relay L to round at the inner rightarmature of relay Relay E in attracting its outer left armaturedisconnects the relay A from the interrupter 109 and closes thefollowing circuit to hold relay A operated; free pole of battery, relay112, conductor 123, relay A, its armature 124 and front contact,conductor 125, uppermost armature and back contact of relay (1,conductor 126, contact 152 of relay E, conductors 128, 153, inner rightarmature of relay Y, conductor 129 to grounded release wire 106. Relay Ein attracting its inner left armature locks itself by way of conductor128 to grounded conductor 106. In attracting its inner right armaturerelay E disconnects relay L from the trunk conductors 116, 119, and inattracting its outer right armature connects the impulse relay I to thering side of the line, and a retardation coil 129 to the tip side. RelayI now energizes over the calling line circuit and operates relay D whichin turn operates relay DD. Relay B operates due to the operation ofrelays I and D and locks to ground at the armature and front contact ofrelay H. The calling subscriber now operates hisdial 130 which causesthe impulse relay I at its left armature to open and close the circuitincluding the impulse relay at the first selector to cause the same tostep the switch up to the desired level in the well-known manner.whereupon it automatically hunts for an idle trunk terminating in aconnector C Upon the first retraction of the rightarma-tures of relay I,re lays D and DD release, relay D'D disconnesting the condensers 131,132 from the outgoing tip and ring conductors to prevent their dischargefrom interfering With the character of the impulses. The relay D is aslow to operate relay as shown, and does not attract its armature duringthe transmission of the impulses. When the selector FS finds and seizesan idle connector C the relay operates over the calling line circuit inthe well-known manner operating the slow relay 203, which in attractingits left armature applies ground to the release wire 2-01, and at itsright armature opens the circuit of the release magnet 206 of theconnector. The calling party now operates his dial to transmit the tensand units impulses to set said connector C on the called line in thewell-known manner, whereupon the line if idle is rung. Upon the responseof the called party the relay 205 operates reversing the direction ofthe current flow in the trunk circuit which operates the polarized relayP in the coin con trol circuit, Fig. 1. Relay P operates relays J and C,the circuit of relay J including its normal left contact, the alternatecontact of relay P to grounded conductor 134:, and the circuit of relayC including the normal contact of relay J to ground over the circuittraced for relay J. The right armatures of relay J are so arranged thatthey operate and shift their contacts before the left armature of saidrelay closes its front contact. Thus the current in the trunk isreversed and relay P again operates to open its contact before the relayJ can close its lef' front contact. Relay J in operating locks to thegrounded conductor 134. Relay in attracting its armature 135 loclrs tosaid grounded conductor. At its uppermost armature it opens the lockingcircuit of relay A. which connects the calling line through to the tipand ring trunk conductors 136, 13? cutting off the impulse relay bridge.Current is now fed to the calling line through the windings of relay204:. Relay (.7 in attracting its armature 138 prepares a circuit fromthe collect source CC. Talking current is fed to the called line overthe windings of relay 205.

The connection is broken down by the replacement ofthe receiver by thecalling party. and the coin is collected automatically at thi time. Theopening of the calling line circuit releases relay 204 which releasesslow relav 203 which at its right armature closes the connector releasemagnet (ircuit and by opening its left contact removes ground from therelease wires 207. 201.. 106 c using the release of the first selectorand relay S. Fig. 1. Relay S in retractino' its outer right armatureoperates relay Y over the following circuit: free pole of battery. relayY. conductor 139. outer c'ht arm ture and back con act of relay 5 nnerght armature and front contact of relay B, conductor 140 to ground atthe front contact of relay H. Relay Y in attracting its outer rightarmature opens the circuit of holding conductor 141 which causes therelease of the secondary line switch SL5. Relay H is slow to release andwhen its circuit leading over conductor 142 is opened by the retractionof the inner right armature of relay S, a substitute circuit 'is closedfor said relay leading over the armature 143 and normal contact of relay A, outer right armature and front contact of relay B, conductor 144,contact 145 of relay Y, conductor 105 to ground at the contact 104 ofthe primary line switch. Relay Y in closing its contact 148 locks itselfto the grounded conductor 134. In attracting its inner right armature itconnects the interrupter 109 to the relay S to intermittently operatethe same. The first operation of relay S operates relay A, this circuitincluding relay 112, conductor 123, relay A, conductor 113, outer leftarmature and front contact of relay 8, inner left armature and frontcontact of relay Y, grounded conductor 134. Relay A in attracting itsarmature 124 locks over conductor 125 to said grounded conductor, andprepares a circuit for connecting the collect source CC to the callingline to collect the coin. The next retraction of the inner left armatureof relay S as the machine 109 reaches an insulated segment causescurrent of 110 volts positive potential to be transmitted from thecollect source CC over the armature and trout contact of relay C,conductor 150, inner left armature and back contact of relay 3, relay L,conductor 116, in parallel over the tip and ring conductors to groundthrough the polarized magnet 111 in the coin box these paths being thesame as those traced when relay L tested for the presence of the coin.This current operates the polarized magnet 111 in the proper dire-tionto collect the coin. If the magnet 'lunctions properly, upon theoperation of relay Fl and the consequent interruption of the collectcurrent. magnet 111 releases causinp the opening of contact 110 asdescribed in detail in said Forsberg patent, thus removing the polarizedmagnet from the tip side of the line. llhe relay L operated in the coincurrent circuit and closed the following substitute circuit for relay Hwhen the circuit for said relay leading over the armature 143 and ba kcontact of relay A w s broken This circuit is as follows: battery. relavH. conduct-or 142, front contact of re ay Ti. conductors and 144,contact 145. conductor 1105. contact 104 to ground. \l'hcn the relav Flnext retracts its armature to close the coin current circuit if themaget 111 has collected the coin and opened he contact 110. relay Lfails to operate and t e substitute circuit for relay H is not closedwhereupon the same releases, its

armature opening the circuit of the holding winding 108 to release theline switch. The function of lamp 154 is to inform an attendant by itssustained illumination that the circuit is not functioning properly.

If the called subscriber does not respond or the line is busy therewould be no reversal of the current in the calling line circult, and therelay P would fail to operate. Relay C is thus not locked up and uponthe replacement of the receiver negative current of110 volts potentialis supplied from the refund source RC to operate the magnet 110 torefund the coin. The relay L tune tions to hold the line switch set ifthe coin is not collected on the first impulse in the same manner asdescribed in the case of a suc-esst'ul call.

Free lines are segregated on connectors with talking current over thewindings of.

the impulse relay 1, the circuit being balanced by the retard coil 1529.Relay DD connects trunk conductors 116 and 119 to the outgoing tip andring conductors, the condensers 131. 132 conductivcly separating thecalling and called ends in accordance with well-known practice. When thecalling party restores his receiver the coin control circuit of Fig. 1functions to refund the coin as described in case the called party didnot answer or the line was busy.

' The function of the left front contact of relay J is to prevent thepossibility of falsely holding the switches set if the called subscriberrestores his receiver first In the arrangement of Fig. 1 when the calledparty replaces his receiver the polarized relay P closes its contact,due to the reversal of the current and shunts out relay J whichreleases, in turn restoring the original connections between the talkingconductors of Figs. 1 and 2, and since then the ground at the coin boxis connected to the upper talking conductor to which the grounded sideof relay 204 is connected, there is no possibility of relay 204remaining energized from the coin ground and preventing release byholding release relay 203 operated.

What is claimed is:

1. In a machine switching telephone sys tom, the combination withtelephone lines, automatic numerical switches for intercon necting thesame, a coin collector at the calling station having a magnet to collector re fund a' deposited coin, means operated by the deposit of a coinand the removal of the receiver at the calling station for connectingboth sides of the calling line to ground through said magnet, meansautomatically operated by the removal of the receiver at the receiver atthe the calling station for extending the calling line to the first ofsaid numerical switches, a normally inoperative impulse circuit forsetting said switches including the calling line, a test relay, acircuit therefor including both sides of the calling linein parallel tosaid ground, means actuated by said relay "for rendering said impulsecircuit operative, and a sender associated with the calling line forcontrolling said impulse circuit to set said switches.

2. In a machine switching telephone sys tom, the combination. withtelephone lines, automatic numerical switches for intercon necting thesame, a coin collector at the calling station having a magnet to collector refund a deposited coin, means operated by the deposit of a coin andthe removal of calling station for con necting both sides of the callingline to ground through said magnet, means auto matically operated by theremoval of the receiver at the calling station for extending the callingline to the first of said numerical switches, a noin'ially inoperativeimpulse circuit including the calling line, a test relay, a circuittherefor including both sides of the calling line in parallel to saidground, means actuated by said relay for rendering said impulse circuitoperative, a sender associated with the calling line for controllingsaid impulse circuit to set said switches, sources of current ofdifferent character at the central ofi'ice, and means operated upon thebreaking down of the connection and dependent upon whether or not thecalled party has responded for impressing current from the proper sourceto operate said magnet to collect or refund the coin.

3. In a machine switching tele hone system, the combination with telepione lines, connecting circuits including automatic numeri-cal switchesfor interconnecting the same, a coin collector at the calling stationhaving a polarized magnet to collect or refund the deposited coin, meansoperated by the deposit of the coin and the removal of the receiver atthe calling station for connecting both sides of the calling line toground through said magnet, means automadcally operated by the removalof the receive-i. at the calling station for extending the calling; lineto an idle connecting circuit, an impulse relay normally disconnectedfrom said connecting circuit, a test relay, a circuit therefor includingboth sides of the calling line in parallel to said ground, meansoperated by said relay for connecting said impulse relay to saidconnecting circuit, and a sender associated with the calling station forcontrolling said impulse relay to set said switches.

l. In a machine switching telephone system, the combination withtelephone lines, conn sting circuits including automatic numericalswitches for interconnecting the same, a coin collector at the callingstation having a polarized magnet to collect or refund the depositedcoin, means operated by the dcposit oi the coin and the removal of thereceiver at the calling station for connecting both sides of the callingline to ground through said magnet, means autoinatically operated by theremoval of the receiver at the calling station for eXtending the callingline to an idle connecting circuit, an impulse relay normallydisconuected from said connecting circuit, a test relay, a circuittherefor including both sides of the calling line in parallel to saidground, means operated by said relay for connect ing said impulse relayto said connecting circuit, a sender associated with the calling stationfor controlling said impulse relay to set said switches, sources oicurrent of diflercnt polarity at the central 056cc, and cleans operatedupon the breaking down of the connection and depending upon whether ornot the ca led party has responded for impressing current from theproper source to operate the polarized magnet to collect or refund thecoin.

5. In a machine switching telephone system, the combination withtelephone lines, connecting circuits including automatic numericalswitches for interconnecting the same, a coin collector at the callingstation having a polarized magnet to collect or re fund the depositedcoin, means operated by the deposit of the coin and the removal of thereceiver at the calling station for connecting both sides of the callingline to ground through said magnet, means automatically operated by theremoval of the receiver at the calling station for extending the callinline to an idle connecting circuit, an impulse relay normallydisconnected from said connecting circuit, a test relay, a circuittherefor including both sides of the calling line in parallel to saidground, means operated by said relay for connecting said in'ipulse relayto said connecting circuit, a sender associated with the calling stationfor controlling said impulse relay to set said switches, sources 01"current of opposite polarity at the central ottice, means controlled bytore calling party for initiating the release of the connection, meansfor delaying the release and auton'iatically applying positive ornegative current from the corresponding source to said polarized magnetto collect or refund the coin dependent upon whether or not the calledparty has answered, and means for complcting the release of theconnection when the polarized magnet operates to dispose of the coin.

(1. in a machine switching telephone system, the combination withtelephone lines, connecting circuits including automatic numericalswitches for connecting the same, a coin collector at the callingstation having a polarized magnet to collect or refund the depositedcoin, means operated by the deposit of the coin and the removal of thereceiver at the calling station for connecting both sides of the callingline to ground through said magnet, means automatically operated by theremoval of the receiver at the calling station for extending the callingline to an ,idle connecting circuit, a test relay, an impulse relaydisconnected from the connecting circuit, a relay operated upon theextension of the calling line to the connecting circuit to open theconnection of the ailing line with the connecting circuit and extend theline to said test relay, said test relay operating in a circuitincluding the sides of the calling line in parallel and said ground toconnect said impulse relay in circuit with the calling line, a senderassociated with the calling line for operating said impulse relay to setsaid switches, means operated by the response of the called party fordisconnecting said impulse relay and test relay from the calling lineand for extending the calling line to the connector,

and means for supplying talking current to the calling and called linesfrom the connector.

7. In a machine switching telephone systom, the combination withtelephone lines, connecting circuits including automatic numericalswitches for connecting the same, a coin collector at the callingstation having a polarized magnet to collect or refund thedepositedcoin, means operated by the deposit of the coin and the removalof the receiver at the calling station for connecting both sides of thecalling line to ground through said magnet, means automatically operatedby the removal of the receiver at the calling station for extending thecalling line to an idle connecting circuit, a test relay, an impulserelay disconnected from the connecting circuit, a relay operated uponthe extension of the callingline to the connecting circuit to open theconnection of the calling line with the connecting circuit and extendthe line to said test relay said test relay operating in a circuitincluding the sides of thecalling line in parallel and said ground toconnect said impulse relay in circuit with the calling line, a senderassociated with the calling line for operating said impulse relay to setsaid switches, means operated by the response of the called party fordisconnecting said impulse relay and test relay from the calling lineand for extending the calling line to the connector, means "forsupolying talking current to the calling and called lines from theconnector, sources of current of different polarity, and means operatedupon the breaking down of the connection and depending upon whether ornot calling line to operate t e coin magnet to collect or refund thecoin.

8. In a machine switching telephone system, the combination withtelephone lines. connecting circuits including automatic numericalswitches for connecting the same, a coin collector at the callingstation having a polarized magnet to collect or refund the depositedcoin, means operated by the deposit of the coin and the removal of thereceiver at the calling station for connect ing both sides of thecalling line to ground through said magnet, means automatically operatedby the removal of the receiver at the callingstation for extending thecallin line to an idle connecting circuit, a test relay, an impulserelay disconnected from the connecting circuit, a. relay operated uponthe extension of the calling line to the connecting circuit to open theconnection of the calling line with the connecting circuit and extendthe line to said test relay, said test relay operating'in acircuitincluding the sides of the calling line in parallel and saidground to connect said impulse relay in circuit with the calling line, asender associated with the calling line for operating said impulse relayto-set said switches, said impulse relay remaining connected to thecalling line when certain lines are called to supply talking current tothe callingline, and means for supplying talking current to the calledline from the connector.

9. In a machine switching tem, the combination with telephone lines,automatic numerical switches for interconnect-ing the same including afirst selector, a coin collector at the calling station having a magnetto collect or refund a. deposited coin, an automatic line switchoperated by the removal of the receiver at the calling station forextending the calling line to the first selector, a holding circuit forsaid line switch controlled by the line relay of the first selector,means operated by the deposit of a coin for grounding the calling line,a test relay adapted to operate in a circuit including said ground,means for disconnecting said first selector from the calling line andsubstituting said test relay therefor and for simultaneously closing abridge to maintain said first selector line relay operated, an impulserelay for setting said numerical switches, means responsive to theoperation of said test relay for connecting said impulse relay inoperative relation to the calling line, and means for automaticallyapplying current to said magnet to collect the deposited coin.

10. In a machine switching telephone system, the combination withtelephone lines,

telephone sys automatic numerical switches for interconnecting the sameincluding a first selector, a coin collector at the calling stationhaving a magnet to collect or refund a deposited coin, an automatic lineswitch operated by the removal of the receiver at the calling stationfor extending the calling line to the first selector, a holding circuitfor said line switch controlled by the line relay of the first selector,means operated by the deposit Off a coin for grounding the calling line,a test relay adapted to operate in a circuit including said ground,means operated upon the extension of the calling line to the firstselector for intermittently disconnecting said first selector line relayfrom the calling line and substituting said test relay therefor and forsimultaneously closing a bridge to maintain said first selector linerelay operated, an impulse relay for setting said numerical switches,means responsive to the operation of said test relay ior connecting saidimpulse relay in operative relation to the calling line where thecalling party may set the switches, and means for applying current tosaid magnet operated upon the breaking down of the connector to collector refund the coin.

11, In a machine switching telephone system, the combination withtelephone lines, automatic numerical switches for interconnecting thesame including a first selector, a coin collector at the calling stationhaving a magnet to collect or refund a deposited coin, an automaticswitch operated by the removal of the receiver at the calling stationfor extending the calling line to the first selector, a holding circuitfor said switch controlled by the line relay of the first selector,means actuated by the deposit of a coin for efiecting a circuit changein the calling line, a test relay operated thereby, means forautomatically periodically disconnecting said first selector line relayfrom said calling line and for substituting said test relay and forsimultaneously closing a bridge to maintain said first selector linerelay operated, an impulse relay for setting said numerical switches,and means responsive to the operation of said test relay for connectingsaid impulse relay in operative relation to the calling line, and meansfor automatically applying current to said magnet to dispose of thedeposited coin.

12. In a telephone system, a. calling line, a sender and call chargingmechanism at the substation thereof, a central otfice in which said lineterminates, an automatic numerical switch thereat, an impulse circuitfor setting said switch, means actuated by the initiation of a call forextending the calling line to said switch, means operated by theactuation of said call charging mechanism for altering the substationcircuit, a test relay at the central oifice responsive to suchalteration for placing said impulse circuit under the control of thesubstation sender, a bridge, means for automatically disconnecting saidswitch from the calling line and for connecting said test relay theretoand for simultaneously connecting said bridge to said switch, said testrelay in operating in response to such alteration permanentlydisconnecting said bridge, and means for subsequently applying currentto said call charging mechanism to operate the same.

In witness whereof, I hereunto subscribe my name this 15th day of March,A. D. 1921 ROY D. CON'WAY.

